Zion National Park officials announced Monday they would extend to the end of the week the public comment period on proposals to implement reservation systems or other means to manage growing crowds.

Park officials released draft plans last month asking the public to comment on a list of "preliminary alternative concepts" that included special permitting processes and a reservation system as possible ways to ease overcrowding in the park, especially its main canyon. Initially the deadline to submit comments was set for Aug. 14.

The park service website, https://parkplanning.nps.gov/zion, was inoperable for a time over the past weekend, due to what officials said was a regularly scheduled maintenance.

Because the public was unable to submit comments while the site was down, the deadline to comment was extended through the end of the day Friday.

Park managers suggest three options in the draft plans, including two that implement some form of year-round reservation system that would apply to either specific sites or all of the park's major attractions.

The process would also involve investigating what exactly the park's visitor capacity should be, which would dictate how many visitors are allowed under the reservation system.

"I want to stress that we have not identified a preferred alternative nor analyzed the impacts of the preliminary alternative concepts at this stage," Superintendent Jeff Bradybaugh wrote in a letter accompanying the report, inviting the public to write in with comments and suggestions.

"Your comments will help us refine the alternative concepts and help guide us in identifying a preferred alternative," he wrote.

The new report is the latest in what figures to be a years-long effort to develop a new management plan for the park amid record visitation and overcrowding.

Through June more than 2.1 million visitors were counted at the park, nearly a 10 percent increase over the same period last year and putting visitation on pace to again set a new record for visitors in a calendar year.

Last year there were 4.3 million over the full 12 months, and Zion moved past Yellowstone National Park to become the 5th-busiest in the country. Since 2010, visitation has jumped by more than 60 percent.

It’s a heavy burden on one of Utah’s most iconic places, wearing down roads and trails, exacerbating issues with trash removal and facility maintenance and casting a bright spotlight on the budgetary problems faced at individual parks thanks to falling federal expenditures.

"Visitors are experiencing long lines for basic services," according to the report, which notes that the park's shuttle system is regularly seeing 95 to 100 people crowding onto buses that are designed to sit 68.

Vehicle traffic at the park's main entrance regularly backs up into the neighboring town of Springdale, search and rescue incidents are at an all-time high and park managers are reporting increased trampling of vegetation and soil erosion. More than 30 miles of unofficial, visitor-created "trails" have been recorded in the main canyon alone.

"Given the changes and the likelihood that interest in visiting the park will continue to increase, a plan is needed to determine how to provide a quality, enjoyable and safe visitor experience while protecting the park's fundamental resources and values," according to the report.

One of the three alternatives proposed is to maintain the current management rules, although authors of the report note that "natural and cultural resources and visitor experience would continue to be degraded."

The two other alternatives propose a registration system. Under one, park managers would set a visitor limit for each day and then require online registration before visiting any "frontcountry" areas in the park, a designation that would require further definition. The second alternative proposes reservation systems for specific sites, especially heavily used trails and crowded areas, along with a permitting system for day-use hikers venturing into wilderness areas outside of the main sites.

The seasonal shuttle system that currently brings visitors into the main canyon would remain in place under each alternative, although schedules could be adjusted. Implementing a new system could require some physical changes and new facilities.

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